The present invention relates to a fuel cylinder mounting structure of a motorcar running by a gas fuel such as natural gas.
Such a fuel cylinder is constructed strong so as to be durable against pressurizing because it stores a natural gas compressed at a high pressure and therefore the fuel cylinder is larger and heavier compared with a conventional gasoline tank.
Usually, the fuel cylinder is mounted in a car body at a place in rear of a rear seat and between right and left rear wheel houses as shown in Japanese Laid-Open Patent Publication No. Hei 7-186741. In this prior art, the fuel cylinder is supported on a rear floor through a chassis frame and a spare tire is placed on the rear floor within a trunk, separately from the fuel cylinder. Rear suspensions under the rear floor are also attached to the car body separately from the fuel cylinder.
In case of the gasoline tank lighter than the fuel cylinder, there is an example in which the tank is attached to the car body from the bottom as shown in Japanese Utility Model Publications No. Sho 62-42863 and No. Sho 50-41627. In this example, the spare tire is also hung on a lower surface of a rear car-body.
According to the above-mentioned Japanese Publication No. Hei 7-186741, when the fuel cylinder is mounted, firstly the chassis frame is attached to the car body at a predetermined position, then the fuel cylinder is brought in through an opening with a rear window removed, placed on the chassis frame and fixed by a fixing band. Therefore, there is required much trouble to attach the fuel cylinder. Moreover, the spare tire and the rear suspension must be attached each separately so that man-our for fitting work increases to lower productivity.
Because package of respective members are also arranged separately and require respective attachment parts, the weight is increased, the cost is raised and the vehicle comes to be large-sized.
In the latter example having the gasoline tank hung, the fitting work is somewhat easy because the gasoline tank and the spare tire are attached to the rear car-body from the bottom. However, rear suspensions must be attached separately, therefore, so much reduction of man-hour of fitting work cannot be expected.
In this example, besides, the gasoline tank has a inclined lower surface projected under the car-body, so that when the spare tire is pushed forward by an external force acting from the rear, the spare tire falls along the inclined lower surface of the gasoline tank to protect the gasoline tank. However, in case of the fuel cylinder which is cylindrical in general, it is difficult to form the lower surface in a inclined surface, moreover it is necessary to protect the fuel cylinder from a flying stone or the like.